Cutter-head drive for last lathes



Apr. 10; 1923. 1,451,665

v c. 1.. LONG CUTTER HEAD DRIVE FOR LAST LATHES Filed Nov. 2'7, 1920 QAEMK \fiik; ATTORNEY.

Patented Apr. ill,

entree stares Parent perms.

CLAUID L. LONG, OF DAYTON, OHIO, ASSIGNOB, TO THE CRAWFORD, McGREG-OR AND CANBY COMPANY, OF DAYTON, OHIO, A CORPORATIUN OF OHIO.

-, CUTTER-HEAD DRIVE FOR LAST LATHES.

Application filed November 27, 1920. Serial No. 426,755,

To all whom it may concern:

Be it known that I, CLAUD L. Lone, a citizen of the United States, residing at Dayton, in the county of lliontgomery and State of Ohio, have invented certain new and useful Improvements in Cutter-Head Drives for Last Lathes, of which the following is a specification.

This invention relates to pattern lathes for turning articles of irregular shape such as shoe lasts, heads for golf clubs, and other variable shapes and forms, and more particularly to a motor drive mechanism and mounting therefor, for driving the cutter heads, which may be mounted upon and travel with the cutter head carriage.

The object of the invention is to simplify the structure as well as the means and mode of operation of such lathes, whereby they will not only be cheapened in construction,

but will be more efficient in operation, positive in action, uniform in result,and unlikely to get out of repair.

A. further object oftheinvention is to eliminate the usual driving drum and the vibration, incident to its use.

A further object of the invention is to provide driving meansfor the cutter heads independent of the motive power of the cutter head carriage, whereby the speed of the carriage and the cutter head, may be varied independent of each other.

A further objectof the invention is to provide positively connected driving means which will eliminate the use of drive belts, and to provide such driving means rigidly upon the cutter head carriage, in intimate relation with the cutter head shaft, whereby a balanced structure will be afforded.

With the above primary and other inci dental objects in view as will more fully appear in the specification, the invention consists of the features ofconstruction. the parts and combinations thereof, and the mode of operation or their equivalents as hereinafte described and set forth in the claims.

Referring to the drawings, Fig. 1 is a top plan view of the head of a pattern lathe, with the reciprocatory carriage mounted thereon, illustrating the application of the improved motor drive mechanism forming the subject. matter. hereofto the present type of lathe. Fig. 2 is aside elevation. taken diagonally in relation with the bed of the lathe, but parallel to the cutter head shaft. Fig. 8 is a detail view illustrating the relation of the driving gear and the motor, taken on line 33 of Fig. 2. Figs. & and 5 are detail plan view and side elevation respectively of a modification of the construction illustrated in the preceding figures. wherein one of the cutter heads is mounted directly upon the armature shaft of the drivingmotor, and the other cutter head shaft operatively connected therewith by inter mediate gears.

Like parts are indicated by similar characters of reference thruoutthe several views.

Inasmuch as the present invention pertains only to the driving meansfor the cutter head shafts, and not to the lathe per so, only such portions of the lathe as are necessary to an understanding of the mechanism and operation. have been illustrated in the drawings. The lathe to which the invention has been shown applied is of the general type illustrated in patent to Eastman, 1,1O i,00, and more particularly that illustrated in pending application Serial No.

196,617 of Long and Schmaus. 1

As illustrated in these prior constructions the cutter head shafts of such lathes have usually been actuated by a drive belt from a large drum located in the lower portion of the lathe structure. some attempt has heretofore been made to eliminate the use of the'large drum. Such constructions have usually retained the belt and the driving, medium. A notable instance of such development is shown. in patent to Morton 1,199,407, wherein a motor issuspended beneath the reciprocatory carriage from which power is transmitted to the cutter head shaft. by a driving belt.

Belts have been found undesirabledue to frequent slippage, and loss of power. and the short life of the belt incident to the high rate of speed, at which the cutter head shafts are driven. It is customary to drive the roughing cutter of the construction shown in the drawings and hereafter described, at an approximate speed of- 6000 R. P. M. while the finishing cutter is rotated at the rate ot 7 500 R. P. M. At such high speeds the slip-,-

page or loss of power is frequently equivalent to from 300 to 500 P. P. M. and friction developed burns a leather belt, so that its average life is approximately ten days. While the fabric belts will last but a few months.

The present construction overcomes these ditliculties by mounting a driving motor on top of the rec-iprocatory carriage, and in juxtaposition to the driving shaft of the cutter head, with which it is interconnected for positive driving action by gears.

Referring to the drawings, 1 is the bed of the lathe having thereon the ways on which reciprocate the model carriage 3, andcutter head carriage 4:. The mechanism for ad v'ancing these carriages in unison is shown and described in theprior patents and pend .ing application heretofore mentioned, to

which reference is to be had for detailed description.

Mounted in suitable bearings 5 in the traveling cutter head carriage isa drive shaft 6, carrying at its extremity a cutter head 7, which may be any suit'al'ile type or construction. The cutter head 6 is inclined to the path of travel of the carriage, whereby the cutter head Trotatesin an oblique :plane and. is advanced laterally against the work. Jounte din similar bearings 9' and extending parallel with the roughing cutter shaft 6 is a shaft 10, also inclined to the path of travel. of the carriage. carrying atits forward end a finishing cutter 11. v The particular construction of the cutternheads 7 and. 11, is described and claimed in the aforementioi'icdpending appl cation of, Long and Schmaus. These cutterheadsare disclosed in the present instance for illustrative purposes only and it is obvious that any other type of cutter head adapted to the work to be performed may be substitutedtherefor. Thebearinp s 5 and 9 for the respective shafts in the present instance have been shown mounted upon a somewhat Z-shaped bracket 12, stationarilv supported upon the traveling carriage 4.

Mounted upon the lower and rearwardly extending shelf or ledge of this bracket 12 is art electric motor 14, upon the armature shaft 15 of which is carried a driving gear 16. The driving gear 16 meshes simultaneously with gears 17 and 18 upon the roughing cutter shaft 6 and finishing cutter shaft 10 respectively. Thedriven gears 17 and 13 are of different diameter whereby the respective shafts aredrivenat differentrates of speed. To insure auniforin driving connectifln these gears are preferably though notnecessarily spiral or helical gears. 3 The driving motor being mounted directly upon thecarriage in lieu of being suspended be neath affords a well balanced construction. and enablesthe power to be transmitted direc ify lpen the... inb el shaft to the cutter head shafts of the interiii shing gears 16, 1?

construction, the driving of the cutter head shaft is accomplished entirely independent of the travel of the carriage, thereby enabling the speed of the carriage and that of the cutter head shaft to be independently regulated, according to the character of the work, or the material operated upon. While the present drivine mechanism is applicable to cutter heads of various sizes, it is especially desirable for driving cutter heads of small size wherein high speeds are necessarily employed.

lVhile in Figs. 1,2 and 3 the intermediate gear 16 has been. shown as the driving gear mounted upon the drive shaft of the motor, there has been shown in Figs. 4: and 5 a modification of this construction, wherein the motor shaft is extended as .the cutter head shaft 6. That is to say, the cutter head shaft 6, bearing/the roughing cutter also comprises the armature shaft of the motor 14, and the roughing cutter 7 is mounted directly upon this armature shaft. The shaft carries the same gear 17, whichin this instance becomes the driving gear meshing with an idlegear 16 mounted upon a suitable bracket 20, attached to the supporting bracket 12. This intermediate idle gear 16 meshes with the gear 18 upon, the finishing cutter shaft, whereby the respective shafts are driven in the same direction, at predetermined relative rates of speed. It is ob vious that'the motor shaftmay be either the roughing cutter shaft or the finishing cutter shaft, in either instance the other shaft being driven thru the medium of the idler ,qear 16.

From the above description it will be apparent that there is thus provided a deviceof the. character described possessing the particular features of advantage before enumerated as desirable. but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantag'es.

While in order to comply with the statute the invention has been described in language that the means and constructibn herein disclosed compr se but one of several modesof putting the inventio'iiinto effect, and the invention is thereforeclaiined in any ef'its torms 'orniod fications within the lglnmatre and valid scope of the appen claims.

Having thus described my invention, I claim:

1. The combination with a pattern lathe including a reciprocatory carriage and a pair of rotary cutter heads mounted thereon, and operable simultaneously on a single piece of work, of a motor carried by the carriage and direct positive driving connections between the cutter heads and motor for driving said cutter heads simultaneously at predetermined relative rates of speed.

2. The combination with a pattern lathe including a reciprocatory carriage, a pair of parallel shafts mounted upon the carriage, a cutter head upon each shaft simultaneously engaging a single piece of work, a toothed gear on each shaft, an intermediate gear simultaneously meshing With both of the shaft gears, and a driving motor directly connected with one of said gearswhegreby the relative rate of rotation of the cutters is uniformly maintained.

3. The combination with a pattern lathe including a reciprocatory carriage and a pair of cutter heads comprising roughing and finishing cutte rs simultaneously operable on a single piece of work and cutter head shafts therefor mounted upon said carriage, of a driving motor carried by said carriage and so connected to drive both cuttelrs that any variation in drive is common to both.

4:. The combination with a pattern lathe including a reciprocatory carriage and a pair of parallel shafts disposed thereon in positions inclined to the path of travel of the carriage, and cutter headscarried by the said shafts and simultaneously engaging a single piece of Work, of a driving motor and means operativefly connecting the driving motor simultaneously with both cutter head shafts whereby said cutter heads Will be rotated at different rates of speed. in unvarying proportion, one to the other.

5. The combination With a pattern lathe including a reciprocatory carriage and a pair of parallel shafts disposed thereon in positions inclined to the path of travel of the carriage, and cutter heads carried by the said shafts comprising roughing and finishing cutters rotating at different rates of speed, a train of toothed gears, operatively connecting the shafts one with the other for simultaneous rotation, a driving motor carried by the carriage and operatively connected with said gear train whereby the relative rotation will be uniform.

In testimony whereof I have hereunto set my hand this 9th day of November A. D. 1920.

CLAUD L. LONG.

Witnesses:

H. B. CANBY, J 01m DINEEN. 

